1. Field of the Invention
The invention relates to a liquid-cooled internal combustion engine, which includes a cylinder housing for at least one cylinder and at least one cylinder head, with the at least one cylinder in the cylinder housing being enclosed by a cooling jacket and with a bottom partial cooling chamber adjacent to a fire deck and an upper partial cooling chamber which is flow-connected with the same via at least one transfer opening arranged in the cylinder head which is connected with the cylinder housing, with a coolant outlet which can be connected with a pressure sink originating from the bottom partial cooling chamber.
2. The Prior Art
A cylinder head is known from AT 005.939 U1 for a liquid-cooled internal combustion engine with a cooling chamber arrangement adjacent to a fire deck, which arrangement is subdivided by an intermediate deck arranged substantially parallel to the fire deck in a bottom partial cooling chamber on the fire deck side and an upper partial cooling chamber adjacent to the same in the direction of the cylinder axis. The bottom and upper partial cooling chamber are flow-connected with each other by at least one transfer opening. A coolant inlet which can be connected with a pressure source opens into the upper partial cooling chamber. A coolant outlet which can be connected with a pressure sink originates from the bottom partial cooling chamber. As a result, the coolant flows in engine operation into the upper partial cooling chamber coming from the pressure source and from there via the transfer opening into the bottom partial cooling chamber and from there to the pressure sink. The coolant further flows from the bottom partial cooling chamber via connecting openings in the fire deck into the cooling jacket of the cylinder housing. The disadvantage is that the region of the liners is not sufficiently cooled. A further disadvantage is that the flow direction from the upper partial cooling chamber via the bottom partial cooling chamber into the cooling jacket of the cylinder housing occurs against the thermosyphon effect in the entire cooling system, which disadvantageously influences the passage of the coolant especially in emergency operation.
It is the object of the invention to avoid such disadvantages and, by using the physical thermosyphon effect, to achieve an improved cooling of thermally critical areas, especially the bottom partial cooling chamber of the cylinder head and the liners.